Does Hastelloy need to be passivated?

After fabrication, yes. Welding, machining and handling embed iron and contaminants that corrode before the base alloy does. Passivation removes them and restores the alloy's designed corrosion resistance.

Should I electropolish or passivate Hastelloy?

Passivate when corrosion resistance is the only requirement and the surface texture does not matter. Electropolish when the surface must also be smoother, brighter, deburred or more cleanable.

Can you oxygen clean Hastelloy components?

Yes. Harrison cleans Hastelloy valves, fittings, piping and vessels for oxygen and industrial-gas service to CGA G-4.1 and ASTM G93 practice and packages them to stay clean.

Which Hastelloy grades do you process?

C-276 and C-22 most often, along with the other Hastelloy grades; send the grade and we will confirm.

Hastelloy: Passivation, Polishing and Cleaning

Fabricated Hastelloy stainless vessel with nozzles after pickling and passivation at Harrison Electropolishing

The short answer: Hastelloy is a family of nickel-chromium-molybdenum alloys (a registered trademark of Haynes International) with high strength and excellent resistance to pitting, crevice corrosion and stress-corrosion cracking — resistance that fabrication partly undoes. Harrison offers every surface process Hastelloy components need: electropolishing to restore corrosion resistance and lower Ra, chemical passivation to remove contaminants without changing the surface, precision mechanical polishing certified as low as 4 µin Ra, and chemical and oxygen cleaning for gas and high-purity service. This page covers passivation, polishing and cleaning; electropolishing has its own page at Hastelloy electropolishing.

Passivation of Hastelloy

Machining, welding and handling embed iron and leave oxides and contaminants that corrode first. Chemical passivation removes them without altering the surface or dimensions, restoring the corrosion resistance the alloy was specified for. Harrison passivates Hastelloy components of all sizes to ASTM A967, ASTM A380 or your company specification, with verification and a certificate of conformance.

Mechanical polishing of Hastelloy

Where a drawing calls for a specified Ra — seal faces, reactor internals, pharmaceutical equipment in C-22 — Harrison mechanically polishes Hastelloy and certifies finishes as low as 4 µin Ra with profilometer readings. Mechanical polishing is also the first stage before electropolishing when the target is lower than electropolishing alone can reach.

Chemical and oxygen cleaning

Hastelloy components for oxygen, industrial-gas and high-purity service are cleaned to CGA G-4.1 and ASTM G93 practice, verified, and packaged to keep them clean; see oxygen cleaning. Chemical cleaning removes process residues, scale and contamination from equipment in service.

Typical components

Reactor internals and columns, heat-exchanger tubes and bundles, valve bodies and trim, pump casings and impellers, scrubber and flue-gas hardware, process piping and fittings, and pharmaceutical and fine-chemical equipment. Large fabrications are handled in Houston with four overhead cranes and 15,000 lb material-handling capacity; installed equipment is passivated and cleaned on-site.

Request a Quote · Call 800-245-5707

More to Know

Frequently Asked Questions

Does Hastelloy need to be passivated?

After fabrication, yes. Welding, machining and handling embed iron and contaminants that corrode before the base alloy does. Passivation removes them and restores the alloy's designed corrosion resistance.

Should I electropolish or passivate Hastelloy?

Passivate when corrosion resistance is the only requirement and the surface texture does not matter. Electropolish when the surface must also be smoother, brighter, deburred or more cleanable.

What finish can you certify on Hastelloy?

Mechanical finishes as low as 4 µin Ra, with profilometer readings supplied.

Can you oxygen clean Hastelloy components?

Yes. Harrison cleans Hastelloy valves, fittings, piping and vessels for oxygen and industrial-gas service to CGA G-4.1 and ASTM G93 practice and packages them to stay clean.

Which Hastelloy grades do you process?

C-276 and C-22 most often, along with the other Hastelloy grades; send the grade and we will confirm.

Request a Quote

800-245-5707

Electropolishing

Harrison Electropolishing, the Leading Electropolishing, Passivation, Oxygen Cleaning & Mechanical Polishing Company World Wide.

Electropolishing is an electrochemical process by which surface material is removed by anodic dissolution. Electropolishing removes surface material, beginning with the high points within the microscopic surface texture. By removing these points, the electropolishing process will improve the surface finish of a metal such as stainless steel, nickel, and Hastelloy, leaving a smoother and more reflective surface. Common parts and components electropolished include tanks, piping, fittings, rods, discs, large parts & surfaces, and more.